Our objective is to use a canine lung cancer model for interdisciplinary clinically relevant surgical research on bronchogenic carcinoma. Existing small animal models neither have cancers like those in man, nor are they practical for innovative diagnostic and therapeutic trials. We have induced sharply localized, endobronchial, predominantly squamous pre-malignant changes in dogs using recurrent transbronchoscopic submucosal injections and/or topical applications of the proven carcinogens 3,4-benzo(a)pyrene and/or N-methyl-N-nitrosourea. Current aims are: (1) To complete the definition of the model to permit following the transition from benignancy to malignancy with predictability; (2) To simplify carcinogenesis; (3) To evaluate multiple site synchronous carcinogenesis. We plan to continue following the existing colony of dogs with the addition of ultrastructural observations. We wish to decrease the expense of carcinogenesis by investigating sustained release submucosal endobronchial carcinogen implants. The synergism between chemical carcinogens and beta radiation in our dog preparation is being evaluated. We plan in the future to use the canine model to supplement studies upon lung cancer in humans.